Not sure if this will help, but I've experience this on the 3.16 kernel & I've put the syslog & kernlog info on pastebin: http://paste.ubuntu.com/10242534/ and attached.
** Attachment added: "systemfreeze.txt" https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1384342/+attachment/4319924/+files/systemfreeze.txt -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1384342 Title: kernel messages intel_crtc_wait_for_pending_flips correlate to compiz hang To manage notifications about this bug go to: https://bugs.launchpad.net/linux/+bug/1384342/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs